astro/astrometry: Remove a source of non-reproducibality

uname -a generates non-deterministic output on some hosts.  It's
used when generating report.txt which is just documentation, so
just don't call it.

PR:		223662
Reported by:	Michael Kotlyar <mdk369@nyu.edu>

astro/astrometry/Makefile

@@ -3,7 +3,7 @@
 
 PORTNAME=	astrometry
 PORTVERSION=	0.65
-PORTREVISION=	4
+PORTREVISION=	5
 CATEGORIES=	astro
 MASTER_SITES=	http://www.astrometry.net/downloads/
 DISTNAME=	${PORTNAME}.net-${PORTVERSION}

astro/astrometry/files/patch-Makefile

@@ -0,0 +1,10 @@
+--- Makefile.orig	2015-12-14 21:13:35 UTC
++++ Makefile
+@@ -309,7 +309,6 @@ tags:
+ 
+ report:
+ 	-uname -m
+-	-uname -a
+ 	-uname -p
+ 	-uname -s
+ 	@echo "CC is $(CC)"